just about to pull the trigger on a Goblin, but debating what size I need. I currently ride a 20 yr old Litespeed Obed titanium frame with a RS Mag21 fork. It's an 18.5 frame(nominally), but actual measures 19 1/4 to the top of the seat clamp. It's been a real long time since I've had a new bike. The problem is that I'm a very long limbed 5' 11 1/2". 35 1/2" inseam crotch to floor in stocking feet, and I need 37 sleeves when i buy dress shirts. So what do you think would be a better fit? An 18 or 20? Oh yeah, my old bike has a 23.2 effective top tube length and is set up with a 135 stem, and due to time marching on, I'm not quite as flexible and it's starting to feel a bit long.